I used Adobe Illustrator to create blueprints of the design. Size was determined by approximating the TARDIS dimensions to be proportional to David Tennant's height. The break-apart design involved inserting four corner posts into the base and attaching three walls, two doors, four Police Box signs and roof via metal bolts. The back wall panel can be removed from the assembled TARDIS to allow performers to enter from the back when appearing onstage or on film.
Actual construction time took about 2 months from start to finish. All carpentry, design, and detailing was done by myself, while several friends helped to paint the blue exterior. I placed LED lights inside the lantern and police signs and hooked them up to a 12 volt lawnmower battery inside the TARDIS so it can be lit without access to an electrical outlet. A set of speakers also attach to this battery to produce the TARDIS sounds, which I created by taking apart a TARDIS toy and making a sound board using the toy's effects. The board is connected to the speakers and hooked up to the lantern, which blinks in time to the sound.
The final outcome was a 15 piece TARDIS that can fit into a minivan or small rental trailer. It takes about 20 minutes to assemble and can be put together with as few as two people. The base houses caster wheels so that the TARDIS can be pushed along even surfaces, such as hotels or convention halls.

Personal Thoughts:

Special thanks to PatrickD, for financially starting this project! And NO, its NOT BIGGER ON THE INSIDE.